The present invention relates to a system for heat-transferring an image printed or vaporized on the surface of a transfer film onto an article such as a cake of soap.
Heat transfer systems are used to apply images to the surface of articles having predetermined shapes unlike ordinary sheets of paper. In such applications, the finish of products is significantly affected by the material forming the articles receiving the image. Pressing force, heating temperature and heating time used for a heat transfer present problems that often result in unacceptable articles. For those reasons, it is sometimes impossible to heat transfer images onto certain articles.
Generally, efficient heat transfer devices have been proposed in which a transfer film retaining an image is pressed against a receiving article by a heated roller. However, in these devices, if transfer speed increases, unevenness in surface temperature of the heated roller occurs, resulting in the production of unacceptable articles. This is caused by the fact that the heated roller loses heat to a receiving article resulting in a reduction in surface temperature which cannot be quickly restored to a desired temperature by a heater disposed conventionally in one location. In attempts to correct this problem, the temperature of the heated roller can become excessive causing the transfer film to become fused to the receiving article.
One technique for alleviating the above noted problem is to increase the diameter of the heated roller to increase its heat capacity and thereby decrease the variation in temperature thereof. However, if the diameter of the heated roller is increased, other disadvantages occur such as lengthly start-up periods and roller overheating during temporary stoppages.
The object of this present invention, therefore, is to provide an improved system for heat transferring an image from a transfer film onto an article such as a cake of soap.